2170421 has 4 divisors (see below), whose sum is σ = 2367744. Its totient is φ = 1973100.

The previous prime is 2170411. The next prime is 2170423. The reversal of 2170421 is 1240712.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 2170421 - 2¹⁰ = 2169397 is a prime.

It is an Ulam number.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2170421.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2170423) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 98645 + ... + 98666.

It is an arithmetic number, because the mean of its divisors is an integer number (591936).

2^2170421 is an apocalyptic number.

It is an amenable number.

2170421 is a deficient number, since it is larger than the sum of its proper divisors (197323).

2170421 is a wasteful number, since it uses less digits than its factorization.

2170421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 197322.

The product of its (nonzero) digits is 112, while the sum is 17.

The square root of 2170421 is about 1473.2348760466. The cubic root of 2170421 is about 129.4736309811.

The spelling of 2170421 in words is "two million, one hundred seventy thousand, four hundred twenty-one".